A method of pretreatment and bromine recovery of PCB Incineration ash is disclosed that relates to the field of comprehensive recovery of valuable metals by full wet method, especially relates to a method of valuable metals and bromine recovery, precious metals enrichment in pretreatment process of PCB Incineration ash. The major steps includes alkali leaching, Cu extraction back-extraction, neutralization-precipitation to separate, Bromine evaporative crystallization, regeneration, acid pickling, Zn evaporative crystallization, removal of Zn and Cu. Compared with the traditional comprehensive recovery process of ash, the invention can separate bromine from ash and recover valuable metals such as copper, zinc and lead with the maximum extent, at the same time, the enrichment of silver and other precious metals is beneficial to the subsequent recovery of precious metals. It has high added recovery value and no tailless discharge.